Protective system



APFEE 9 M36 L. R s RAsBuRGER 2,037,39g

PROTECTIVE SYSTEM Filed July 12,1934

Patented Apr. 14, 1936 UNITED STATES PATENT OFFICE- Lester R. Strasburger, Washington, D. O.

Application July 12, 1934, Serial No. 734,871

4 Claims.

The present invention relates to a system for protecting stores against robbery and burglary by discharging irritating gases, for example tear gases or the like, into the space which is about to be robbed. The object of the invention is to providea system which will automatically discharge such irritating gases upon the unauthorized forced entry into the protected space. More specifically, the present system is so arranged that when the burglar seeks to obtain a forced entry intothe protected space such as by breaking the window of a window display in a store the system will then operate to discharge such irritating gases in the display space and some of these gases will flow through the hole in the window and will incapacitate the robber. The gas device may contain a mixture of gases such as tear gas or the like and smoke gas.

With ,these general objects in mind, further objects and advantages will be apparent from the following description which refers to the accompanying drawing; it being understood that the specific embodiments of the invention set forth herein are illustrative and do not serve to limit the invention and that variations of theembodiments shown herein and falling within the scope of the appended claims will be apparent to persons skilledin the art. In the draw- 7 ing Fig. 1 is a diagrammatic showing of the system employing a gasdischarge device of the type which is provided with electric ignition. Fig. 2 shows a similar system in which the gas device is provided with a trigger operated ex- 7 plosive cap. Fig. 3 shows a system designed to be operated on commercial current. Fig. 4 shows anoither system for operation on commercial curren Fig. 5 shows the system of Fig. 4 provided with a trip circuit breaker. V Y I The invention in its simplest form is diagrammatically illustrated in Fig. 1. A conducting tape I I is applied to the window pane shown in dotted lines in such a manner that when the window is brokenthe tape will break and thereby open the normally closed electrical circuit which includes the source of current I2, the conductors I3 and l4 and the relay I5. The relay I5 is normally energized by this closed circuit and thereby maintains its armature I6 in its open position. I! indicates a gas discharge device of the type which is provided with electrical ignition whether it be in the form of a fuse, a spark or a heating wire for. the purpose of discharging. Such gas cartridges are generally provided with some explosive which serves to explode the gas or gas-generating solid or liquid, as the case may be, into the space or display compartment which very rapidly fills the space with the irritating gas or a mixture of such gases. The electrical discharge device is diagrammatically indi- 5 cated by reference character I8.

It will now be understood tha-twhen the window pane is broken the circuit of therelay I5 is opened and the relay I5 thereby becomes deenergized. The armature I6 then drops to close the circuit with the contact I 9 and the electrical ignition I,8,then receives current from the source l2 through the wires 20 and 2I.. .One ofthese wires may, if desired, include a current limiting resistance 60. The mixture of gases, ifdesired, may also contain a smoke gasso that the contents of the space or compartment become invisible. This discharges the gas cartridge and. the protected space is immediately filled with the irritating gasand the gas escapes through the hole in the window and attacks and incapacitates the robber. g I

Another type of gas discharge device that may be employed is of the kind which is discharged bymeans of a trigger blow in that in addition to the gas generating material, itfcontains explosive material and a detonating cap. I Fig. 2 shows a, system in other respects identical with that shown in Fig. 1 but employs the latter type of discharge device which is diagrammatically 30 shown by reference character I'II. In this system, however, a solenoid I8I is employed to operate the plunger 22, which serves to strike the detonating explosive cap in cartridge Ill and thereby discharge the gas or gas generating material into the space protected by the broken tape II.

The systems shown in Figures 1 and 2 may be employed in local installations in which a local source of current I2 is employed. The source of power I2, as shown in Figures 1 and 2, is permanently connected to the protective installation and is not to be disconnected from the system except by a skilled and authorized person at the installation and he will not disconnect or reconnect the source of power to the system without first removing the gas cartridge. This precaution has to be taken for the reason that should one disconnect the source of current from the installation and then reconnect it to the in- 50 stallation, without first removing the gas discharge device, the gas device is likely to be discharged unnecessarily.

However, it may be desired to provide the current for such installations by connecting the same 55 v with the commercial source of current, which may be available at the installation. It is well-known that such commercial sources of current are frequently disconnected and reconnected at the central operating stations of the public utilities. The system shown in Fig. 3 is designed for operation from a commercial source of current. The source of current is shown at AB. The transformer 23 is interposed between the source of current AB and the conducting tape II for the purpose of applying a low voltage to such tape. It is ob Vious that an analogous device for reducing the voltage may be employed in lieu of transformer 23 in such cases where the source of current AB is direct current. The relay I5I is in series with the conducting tape II and is the usual or fast acting relay. This relay is normally energized and thereby maintains its armature I6I in the open position and the relay 24 is thus maintained deenergized, the relay 24 being connected on one side to the contact I9I of the relay I5I and on the other side by means of conductor 62 to conductor I3. Relay 24 being normally deenergized, its armature 25 is normally in its open contact position. I12 in Fig. 3 is a diagrammatic showing of the gas discharge device together with its operating element. The device shown herein may be either of the type which is electrically ignited. as shown by Fig. 1, or it may be of the type which is ignited by a trigger blow, and I12 is then also intended to include the solenoid for its operation. The fixed contact 26 of the relay 24 is connected by wire 21 to one side of the gas device I12, the other side of the gas device being connected to one side of the source of current by the wire 28, which may include a current limiting resistance 60. The armature 25 is connected to the otherside of the source of current by conductor 29.

In the system shown in Fig. 3, the relay' I5I being normally energized, its armature IGI is normally in the open circuit position. The relay 24 is therefore normally deenergized and its armature 25 is normally in the open circuit position. However, as soon as the window is broken and its protective tape H is broken, relay I 5I deenergizes thereby causing its armature IBI to drop to the closed circuit position and relay 24 becomes energized. Its armature 25 is then drawn to the closed circuit position and the gas device I12 is operated to discharge gas into the protected space and flows through the hole in the window to disable the robber.

The relay 24 is a retarded or slow acting relay. By means of the use of this system employing the slow acting relay 24, the possibility of the'gas device being discharged by reason of the opening or closing of the main switches of the central power station is eliminated. In such event the closing of the main switches of the central power station will cause relay I 5| to move its armature IBI to its open circuit position before the operation of the retarded or slow acting relay 24.

It will be understood that the conductors 28 and 29, while shown as connected to the low voltage side of the voltage reducing device 23, may if desired be connected to the high voltage side. This will depend upon the nature of the ignition device employed in the gas device I12.

While the system shown in Fig. 3 may be employed either for the type of gas device which is provided with an electrical ignition or it may be employed for the type of gas device which is discharged by means of a plunger operated by a solenoid, the present invention also contemplates the use of a solenoid so constructed and arranged that it may be employed in the system shown in Fig. 2 and at the same time prevent the accidental discharge of the gas device, by reason of the disconnection and reconnection of the source of current to the system. For this purpose the solenoid may be so selected for its electrical characteristics that it will operate more slowly than the relay I5; or if desired the solenoid may be provided with a mechanical retarding device such as a spring or the like.

Fig. 4 shows a system of this type and specifically discloses a vertically disposed solenoid and vertically movable plunger. The latter is provided with a spring which serves the double function of retaining it in its normal position and also serves as a retarding device. This figure also shows the detail construction of a unitary assembly adapted to be mounted in an opening in the ceiling or side wall of the display compartment. The system shown in Fig. 4 comprises the conducting tape II, relay I5 in series therewith, and the voltage reducing device 23. The solenoid 30 is connected on one side to the commercial source of current through the armature I6 of the relay I5, and on the other side is connected to the commercial source of current through the armature 3| of the relay I5. In order to prevent the accidental discharge of the gas device I H the solenoid may be so selected for its electrical characteristics that it will operate more slowly than relay I5, with the result that the armatures I6 and 3| will be moved to their open positions before the plunger 32 will have acquired suflicient momentum to operate the gas discharge device I1I.. If desired, however, a solenoid of any type may be employed and the plunger 32 provided with an end plate 33 and a spiral spring 34 disposed between the end plate 33 and the upper end of the solenoid 30. The spring 34 serves as a retarding device for the plunger and prevents the operation of the plunger upon the gas device when the main switch of the central power station is thrown on.

The systems shown in Figures 1 to 4 may continue to draw current after operation. If desired, a trip circuit breaker may be interposed in the lead wires to the solenoid shown in Fig. 4 so as to break this circuit. This is shown in Fig. 5. A trip circuit breaker 35 is provided in series with the solenoid 30, the same being operable by the collar 33 during the downward movement of the plunger 32 and immediately preceding the completion of the stroke of the plunger. This is for the purpose of preventing the current from staying on for a long time after the operationof the device and before an authorized person arrives to put the system back into its operative condition. The trip circuit breaker is so designed with relation to the plunger and its collar 33 that it is operated during the last fraction of its movement downward Without interfering with the completion of its movement, or after it has acquired sufiicient momentum to complete its stroke even after the circuit is broken. For this purpose the trip circuit breaker comprises a bell crank lever, pivoted at 36 and having a contact arm 31 and a trip arm 38. The end of the trip arm 38 is disclosed as shown in the path of the collar 33 and is so spaced therefrom that immediately prior to the completion of the stroke of the plunger 32 the collar 33 strikes the end of the arm 38 and the lever is pivoted about 36, with the result that it is removed from under the horizontal contact arm 39. The arm 39 is pivoted about 40 and the movement of the bell crank lever permits the arm 39 to drop to the inoperative dotted line position. The circuit of the solenoid is thereby broken and remains broken until an authorized person appears to place the system in its operative condition. It will be understood, however, that the system may be employed without the use of the trip circuit breaker 35.

The solenoid unit shown in Fig. 4 may be constructed as a unitary assembly which may be mounted on the ceiling or wall of a window display compartment. In the drawing the ceiling is indicated at 4| and is provided with the opening 42. The assembly comprises the annular metal plate 43 having an opening 44 and a downwardly directed annular fiange 45 at such opening. This flange is exteriorly threaded and is designed to receive the rim 4! of the gas discharge device Ill between the interior shoulder of the collar 46 and the end of the flange 45. Solenoid 3B is mounted on the upper face of the plate 43 by means of screws or bolts 48. When the system is provided with the trip circuit breaker, the upper face of the plate 43 may carry a pair of standards 49 which support the trip circuit breaker 35 and its associated devices. The plate 43 is also provided with a peripheral fiang'e 50 which supports a canopy in any manner desired. It will now be seen that this constitutes a unitary assembly which may be mounted against the ceiling M by means of the screws or bolts 52.

It will be understood that the trip circuit breaker 35 may be provided with two pairs of cooperating contacts, one in each of the lead wires to the solenoid.

The conducting tape II, which is applied to the window pane, may be either in the form of a metallic tape or it may be in the form of a conducting metallic paste, or paint. I have found that the metal paste, consisting of finely divided metal dispersed through a plastic material which dries and hardens on exposure to the air, is readily applied to the window and is highly useful for the present purposes.

Window displays generally constitute closed and limited compartments. By means of the system shown herein a burglar who attempts to gain access to this compartment by breaking the window will automatically set off the gas device, which will be promptly discharged in such a manner as to fill the compartment with an irritating gas or a mixture of such gases. Such gas will immediately flow through the opening in the window and attack the burglar and thereby incapacitate him from any further action. If desired, an alarm bell 6| may be connected in the circuit and operated simultaneously with the gas device. Such alarm bell may be located near the outside of the premises or at a central station or both.

The systems shown in Figures 3, 4 and 5, while as shown are intended for use with a commercial source of current, may also be employed with a local source of current.

I claim:

1. In combination with a store display window, a closed display compartment disposed behind such window, the window forming the front wall of said compartment, a protective system therefor comprising a source of current, a normally closed circuit connected to said source of current and including a frangible conductor mounted on said window, a disabling gas discharge device disposed in said compartment, and means operatively associating said device with said circuit whereby a breach in the window will open said circuit and cause said device to discharge disabling gas into the compartment and through the breach.

2. In combination with a store display window, a closed display compartment disposed behind such window, the window forming the front Wall of said compartment, a protective system therefor comprising a source .of current, a normally closed circuit connected to said source of current and including a frangible conductor mounted on said window, a disabling gas discharge device disposed in said compartment, a second normally open circuit connected to said source of current, a normally energized relay in said first circuit for maintaining said second circuit normally open, a slow acting relay in said second circuit, and a normally open third circuit controlled by said slow acting relay, and means in said third circuit operable by a breach in the window to cause said device to discharge disabling gas into the compartment and through the breach.

3. In combination with a store display window, a closed display compartment disposed behind such window, the window forming the front wall of said compartment, a protective system therefor comprising a source of current, a normally closed circuit connected to said source of current and including a frangible conductor mounted on said window, a disabling gas discharge device disposed in said compartment, a second normally open circuit connected to said source of current, a normally energized relay in said first circuit for maintaining said second circuit normally open, and means operable by a breach in the window to cause said device to discharge disabling gas into the compartment and through the breach, said means comprising a slow acting electrical device in said second circuit.

4. In combination, a store window, a closed display compartment disposed behind said window, the window forming the front wall of said compartment, a disabling gas discharge device disposed in said compartment, and electrical means associated with said window whereby a breach in the window will affect the electrical means to cause said device to discharge disabling gas into the compartment and through thebreach.

LESTER R. STRASBURGER. 

